ldquoConventionalrdquo techniques and related capacitance-voltage characteristic interpretation were established to evaluate interface trap density on Si substrates. We show that blindly applying ...these techniques on alternative substrates can lead to incorrect conclusions. It is possible to both under- and overestimate the interface trap density by more than an order of magnitude. Pitfalls jeopardizing capacitance-and conductance-voltage characteristic interpretation for alternative semiconductor MOS are elaborated. We show how the conductance method, the most reliable and widely used interface trap density extraction method for Si, can be adapted and made reliable for alternative semiconductors while maintaining its simplicity.
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•The impact of electrically active defects on the electrical characteristics of Ge in STI Si diodes has been investigated.•The presence of threading dislocations and associated deep ...acceptors has a marked impact on the electrical characteristics.•The DLTS response is related to electron repulsive centers located at ∼0.33–0.40eV below the conduction band.
In this work, the temperature behavior of the transport mechanisms present in Ge p+n junctions selectively grown in shallow trench isolation (STI) substrates is investigated. Special attention is given to the impact of electrically active defects on the current–voltage (I–V) and capacitance–voltage (C–V) characteristics. Moreover, deep level transient spectroscopy (DLTS) is performed in order to evaluate the electrical properties of the traps. The results show that the presence of threading dislocations and associated deep acceptors has a marked impact on the electrical characteristics. The DLTS response seems to be related to electron repulsive centers with an acceptor character located at ∼0.33–0.40eV below the conduction band. This mid-gap position yields very effective Shockley–Read–Hall centers and can explain the generation lifetime reduction and leakage increase observed in non-annealed Ge in STI Si diodes.
Vasomotor symptoms affect 60-80% of women during the menopausal transition. Anxiety, depression, and anxiety sensitivity can have an important role in the distressful experience of vasomotor ...symptoms. Our aim was to evaluate the prevalence and association of vasomotor and negative affect symptoms.
A cross-sectional study was conducted with 89 perimenopausal women aged 45-55 years. Broad psychiatric and clinical evaluations were carried out. The primary outcome was the vasomotor symptom problem rating and the main study factor was anxiety sensitivity. Linear regression analyses were conducted to examine the associations between the study factors and the primary outcome, and a multiple regression model was created to assess which variables were independently associated with vasomotor symptom problem rating.
The prevalence of anxiety, depression, and vasomotor symptoms were 58, 62, and 73%, respectively. Negative affect symptoms were positively associated with vasomotor symptom problem rating. The association of anxiety sensitivity and vasomotor symptom problem rating remained significant after controlling for perimenopausal stage, thyrotropin, follicle-stimulating hormone levels, and psychotropic medication use (β = 0.314, p = 0.002).
A better understanding of the experience of vasomotor symptoms is needed, especially the role of negative affect symptoms and anxiety sensitivity. New strategies focusing on related thoughts and behaviors could improve the quality of life of perimenopausal women.
In this paper, we report on the challenges related to growth and processing of 200 mm GaN-on-Si wafers in a CMOS fab. We describe the Au free process we developed as well as how we assure wafer ...quality prior processing. For the first time, we analyze possible Ga contamination issues related to the processing of GaN wafers and we present the cleaning procedures we developed to avoid it.
This paper presents an analysis of junction leakage in heavily doped p+/n germanium junctions, targeted for short-channel transistor fabrication. There exists an optimal p+/n junction condition, with ...a doping concentration of 1 times 10 17 -5 times 10 17 cm -3 , where the area-leakage-current density is minimal. Use of a halo-implant condition optimized for our 125-nm gate-length pMOS devices shows less than one decade higher area leakage than the optimal p+/n junction. For even higher doping levels, the leakage density increases strongly. Therefore, careful optimization of p+/n junctions is needed for decananometer germanium transistors. The junction leakage shows good agreement with electrical simulations, although for some implant conditions, more adequate implant models are required. Finally, it is shown that the area-junction static-power consumption for the best junctions remains below the power-density specifications for high-performance applications.
Ge pMOSFETs with HfO 2 gate dielectric and gate lengths down to 125 nm are fabricated in a Si-like process. Long-channel hole mobilities exceed the universal curve for Si by more than 2.5 times for ...vertical effective fields as large as 1 MV/cm. The mobility enhancement is found to be relevant at submicron gate lengths, and a drive current of 1034 muA/mum is achieved for L=125 nm at V G -V T =V D =-1.5 V. The introduction of halo implants allows significantly improved control of short-channel effects, with approximately three orders of magnitude reduction in source junction off-current. V T rolloff and drain-induced barrier lowering are reduced from 207 mV and 230 mV/V to 36 mV and 54 mV/V, respectively, for the highest n-well dose investigated. Four key logic benchmarking metrics are used to demonstrate that Ge is able to outperform Si down to the shortest investigated gate length, with an almost twofold improvement in intrinsic gate delay. I ON =722 muA/mum is demonstrated for I OFF =11 nA/mum at a power supply voltage of -1.5 V, when evaluating from the source.
Variants of the C19ORF12-gene have been described in patients with spastic paraplegia type 43 and in patients with mitochondrial membrane protein-associated neurodegeneration (MPAN), a subtype of ...neurodegeneration associated with brain iron accumulation (NBIA). In both subtypes optic atrophy and neuropathy have been frequently described. This case report describes a patient with bilateral optic atrophy and severe distal muscle weakness based on motor neuropathy without involvement of the central nervous system. Exome sequencing revealed a homozygous pathogenic missense variant (c.187G>C;p.Ala63Pro) of the C19ORF12-gene while iron deposits were absent on repeat MR-imaging of the brain, thus showing that peripheral neuropathy and optic neuropathy can be the sole manifestations of the C19ORF12-related disease spectrum whereby iron accumulation in the brain may be absent.
•C19ORF12 variants have been described in mitochondrial membrane protein-associated neurodegeneration.•Central nervous system features predominate but optic neuropathy and peripheral neuropathy are frequently found.•Peripheral and optic neuropathy can be the sole manifestations.
A commercial technology computer-aided design device simulator was extended to allow electrical simulations of sub-100-nm germanium pMOSFETs. Parameters for generation/recombination mechanisms ...(Shockley-Read-Hall, trap-assisted tunneling, and band-to-band tunneling) and mobility models (impurity scattering and mobility reduction at high lateral and transversal field) are provided. The simulations were found to correspond well with the experimental I- V data on our Ge transistors at gate lengths down to 70 nm and various bias conditions. The effect of changes in halo dose and extension energies is discussed, illustrating that the set of models presented in this paper can prove useful to optimize and predict the performance of new Ge-based devices.
AlGaN/GaN MIS‐HEMTs with two levels of source field‐plates were studied by means of pulsed I–V measurements. These measurements showed that the presence of a source field‐plate itself is not enough ...to guarantee a low dynamic RDS‐ON at high OFF‐state drain‐bias. Simulations of the electric field were carried out to explain the experimental results. It was found that not only does the intensity of the electric field affects the dynamic RDS‐ON, but also that the position of the electric field peaks plays a role in the trapping phenomenon, responsible for the dynamic RDS‐ON increase at high OFF‐state drain‐bias. These results show that the source field‐plate must be carefully designed in order to obtain a low dynamic RDS‐ON at high bias.
This paper provides an overview of the current state-of-the-art in the formation of shallow junctions in germanium by ion implantation, covering the issues of dopant activation, diffusion and defect ...removal. As will be shown, for the case of p
+ implantations, the application of rapid thermal annealing (RTA) to B implants yields good sheet resistance values, corresponding with activation levels well above the maximum solid solubility. A further improvement can be achieved by the use of a Ge pre-amorphization implant (PAI), which also removes the stable extended defects observed after high-dose B implantations. It will be shown that the formation of shallow n
+ junctions is a more challenging field due to the rather low dopant solubilities and high diffusivities. However, encouraging results will be reported on the application of laser and flash-lamp annealing of P implantations in Ge. Also point-defect engineering is shown to be successful in controlling the junction formation.
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